5. Select the first board from your new set (e.g. "ATmega168 @ 16 MHz")

6. Click Verify

7. Open Explorer (the thing used to browse the harddrive)

8. Navigate to the temporary directory; in Windows the path "%TEMP%" gets you there.

9. In a sub-directory in the temporary directory, locate the corresponding dot-hex file. If the sketch is named "sketch_feb28a" the dot-hex will be named "sketch_feb28a.cpp.hex".

10. Copy the dot-hex file.

11. Navigate to the "Arduino/hardware/arduino/bootloaders" directory.

12. Create a sub-directory named "empty".

13. Navigate into the "empty" sub-directory.

14. Paste the dot-hex file.

15. Rename the dot-hex file to something appropriate for the board like "empty168at16.hex". This filename is the value for the "bootloader.file" entry in "boards.txt".

16. Switch to the Arduino IDE.

17. Select the next board (e.g. "ATmega168 @ 8 MHz").

18. Click Verify

19. Switch to Explorer

20. Navigate to the temporary directory (%TEMP%)

21. In a sub-directory in the temporary directory, locate the corresponding dot-hex file. If the sketch is named "sketch_feb28a" the dot-hex will be named "sketch_feb28a.cpp.hex".

22. Copy the dot-hex file.

23. Navigate to the "Arduino/hardware/arduino/bootloaders/empty" directory.

24. Paste the dot-hex file.

25. Rename the dot-hex file to something appropriate for the board like "empty168at8.hex".

26. Repeat steps 16 through 25 for any additional boards.

27. Close and restart the Arduino IDE.

It is now possible to change the fuse settings with impunity...

1. Select one of the new boards (like "ATmega168 @ 16 MHz").

2. Click Tools / Burn Bootloader.

The fuse settings are changed and an empty / do nothing sketch is uploaded. The processor is "hardware safe" and ready with the new fuse settings. For more examples, refer to the Tiny Core boards.txt file and "bootloaders"...http://code.google.com/p/arduino-tiny/

Just curious about the BOOTRST fuse bit.If I understand correctly, when this bit is programmed, it executes the bootloader code, and then the application code after a reset?If the bit is unprogrammed, then it executes the application code immediately after a reset?

So I assume, when you normally have a bootloader present, you want BOOTRST programmed?But in this case, I assume it doesnt really matter since the bootloader file is blank?